1. Field of the Invention
The present invention relates to a light pen, and more particularly to a pen that receives a luminous bar therein to provide a warning signal.
2. Description of Related Art
People generally use a flashlight or a candle for emergency illumination. However, the flashlight can not be used when the battery is dead or the bulb is burned out and the candle may easily to cause a fire. To solve the above mentioned problems, a luminous bar was thus invented.
The luminous bar has a housing made of a transparent plastic, such as a polyethylene. A chemical liquid is in the housing. A sealed glass tube is also in the housing and provides another chemical liquid therein. When the glass tube is broken by bending the bar, the two chemical liquids are mixed together to generate light by a chemical reaction of the two liquids. The light will continue to illuminate a long time and will not harm the user.
With this feature, the luminous bar can be used for a warning signal when an emergency such as a failure of electrical system of an automobile at night. However, it is inconvenient to carry the luminous bar because it is easy to break. Therefore, this problem limits the use of the luminous bar.
Therefore, the present invention tends to mitigate and/or obviate the aforementioned problem by providing an improved pen having a luminous bar.